Many engine systems include an exhaust aftertreatment system for treating the exhaust exiting the engine. Exhaust aftertreatment systems can include a variety of components and subsystems for treating the exhaust, such as a diesel oxidation catalyst, a diesel particulate filter, selective catalytic reduction system, and an ammonia oxidation catalyst.
In some engine systems, the exhaust conduit or pipe used to transfer exhaust from the engine to the exhaust aftertreatment system may include internal structure, such as baffles or vanes, to condition the flow of the exhaust or aid in treating the exhaust. In the system of German Patent Publication No. 102012021017A1, to Braun et al., three baffle elements are welded to a transfer pipe or interior wall of a first exhaust gas duct. The baffle elements are spaced apart in the direction of the longitudinal axis of the transfer and parallel to one another. A reducing agent injector is arranged such that the injection stream at least partially impinges onto a major baffle surface of each of the baffles.